Fault detection and isolation for a wind turbine benchmark using a mixed Bayesian/Set-membership approach

This paper addresses the problem of fault detection and isolation of wind turbines using a mixed Bayesian/Set-membership approach. Modeling errors are assumed to be unknown but bounded, following the set-membership approach. On the other hand, measurement noise is also assumed to be bounded, but following a statistical distribution inside the bounds. To avoid false alarms, the fault detection problem is formulated in a set-membership context. Regarding fault isolation, a new fault isolation scheme that is inspired on the Bayesian fault isolation framework is developed. Faults are isolated by matching the fault detection test results, enhanced by a complementary consistency index that measures the certainty of not being in a fault situation, with the structural information about the faults stored in the theoretical fault signature matrix. The main difference with respect to the classical Bayesian approach is that only models of fault-free behavior are used. Finally, the proposed FDI method is assessed against the wind turbine FDI benchmark proposed in the literature, where a set of realistic fault scenarios in wind turbines are proposed.Peer Reviewe

Sintonización automática de filtros de microondas mediante motores a pasos

Este artículo describe un sistema para sintonizar filtros de microondas de manera automática. Se presentan los resultados obtenidos de la sintonización automática de un resonador de microondas mediante un sistema diseñado específicamente para tal propósito. Este sistema es extrapolable a filtros de microondas que requieren múltiples tornillos de sintonización. El sistema diseñado se encarga de pedir al usuario los datos necesarios, procesar las medidas realizadas y finalmente hacer girar un motor a pasos para conseguir el ajuste deseado de frecuencia de resonancia. El tornillo de sintonización está unido al motor a pasos, y al girar el motor se hace variar la frecuencia del resonador. Dependiendo del paso del motor se podrá conseguir mayor precisión en el ajuste, pero lo que se mejora sustancialmente es el tiempo invertido en la sintonía y la velocidad a la que se puede cambiar la respuesta del dispositivo.Peer Reviewe

Data Analysis for the Development of an Automatic Vessel Control System in a Port Area

[Resumen] Según el último informe de la Agencia Europea de Seguridad Marítima (EMSA), un gran número de incidentes de navegación con víctimas se producen en instalaciones portuarias. Para minimizar el número de accidentes es necesario contar con algoritmos de control eficientes que permitan decidir acciones en tiempo real por parte del operador. Se presentan las principales fuentes de los datos que permiten un control efectivo del control portuario. Se discuten las ventajas e inconvenientes de los datos suministrados por los sistemas AIS y RADAR. A partir de los requerimientos de seguridad para evitar colisiones, se analizan los principales datos relacionados con la embarcación y su entorno que son relevantes para un algoritmo eficiente del control de tráfico en puertos.[Abstract] According to the latest report from the European Maritime Safety Agency, a large number of boating incidents with casualties occur at port facilities. To minimize the number of accidents, it is necessary to have efficient control algorithms that allow the operator to decide actions in real time. The main sources of data that allow an effective control of port control are presented. The advantages and disadvantages of the data supplied by the AIS and RADAR systems are discussed. Based on the safety requirements to avoid collisions, the main data related to the vessel and its environment that are relevant for an efficient algorithm of traffic control in ports are analyzed.https://doi.org/10.17979/spudc.978849749804

An Open Source Multiplatform Virtual Laboratory for Engineering Education

An autonomous and multiplatform virtual laboratory for educational purposes is presented. The implemented platform includes a server with a SSH (Secure SHell) connection and a separated repository containing the virtual experiments. The programming of the experiments is implemented in Java language based tool, the EJS (Easy Java Simulation) and uses an external computation engine, for example Matlab. The virtual laboratory provides control system experiments at University level. Two application examples are described, namely, a magnetic levitator and an inverted pendulum-cart system. The virtual laboratory has been successfully used for education and training of Electronics Engineering students. A discussion of the results of this e-learning experience is also presented

Some properties of PRMA

PRMA - Packet Reservation Multiple AccessSIGLEAvailable from British Library Document Supply Centre- DSC:4335.26205(HPL--93-85) / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Incremental upgrading sensor placement methodology: Application to the leak localization in water networks

This paper presents a new methodology for sensor reallocation in large scale-systems considering fault isolation purposes. From an initial set consisting of a limited number of sensors already installed in certain locations of the system, the proposed methodology produces a new sensor placement where some of the sensors are strategically reallocated in different but available places of the system. The procedure is posed as an optimization problem where the performance index is specific of the fault isolation method to be used. The algorithm that solves the problem is an incremental upgrading approach based in the Sequential Forward Floating Search algorithm and it combines a forward phase (where sensors are added sequentially) with a backward phase (where sensors can be individually removed from the original sensor placement). The proposed methodology is illustrated by means of its application to the problem of leak localization in Water Distribution Networks (WDN), where the particular placement of the pressure sensors has a great impact in the ability to isolate the leaky node. Also, since only a limited number of pressure sensors can be installed in some nodes, space interpolation techniques must be used to estimate the pressure in the other network nodes. The performance of the localization process is measured in terms of pipe distance from the estimated leaky node candidate to the real leaky node. The proposed methodology is applied to two District Metered Areas of the WDN of a metropolitan area of Spain, in simulation and using real measurements and leak scenarios.This work has been partially funded by L-BEST Project (PID2020-115905–RB-C21) funded by MCIN/ AEI /10.13039/501100011033, by the European Commission through contract EFFINET (ref. FP7-ICT2011-8-318556), and by the Catalan Agency for Management of University and Research Grants (AGAUR), the European Social Fund (ESF) and the Secretary of University and Research of the Department of Companies and Knowledge of the Government of Catalonia through the grant FI-DGR 2015 (ref. 2015 FI_B 00591)

Development of a Simulation Environment for the Learning of an Autonomous Navigation Algorithm for a 2-Meter Length Sailboat

[Resumen] Se presenta el desarrollo de un entorno virtual de simulación basado en Python Turtle para el entrenamiento de un algoritmo de aprendizaje por refuerzo destinado a la navegación autónoma de un velero de 2 metros de eslora. Este entorno de simulación permite entrenar el pilotaje autónomo en diferentes condiciones de viento y datos de navegación de la embarcación, en ausencia de obstáculos, por medio de la observación causa-efecto y una estrategia de recompensas que permiten al agente decidir las mejores acciones. La generación virtual de situaciones de navegación reduce las horas de pruebas de mar.[Abstract] The development of a virtual simulation environment based on Python Turtle is presented for the training of a reinforcement learning algorithm for the autonomous navigation of a 2 meters long sailboat. This simulation environment enables autonomous piloting to be trained in different wind conditions and navigation data from the vessel, in the absence of obstacles, through cause-effect observation and a reward strategy that allows the agent to decide the best actions. The virtual generation of navigation situations reduces the hours of sea trials.Los autores agradecen a la Facultat de Náutica de Barcelona la ayuda económica para la realización del proyecto Sensailorhttps://doi.org/10.17979/spudc.9788497498043

Leak Localization Method for Water-Distribution Networks Using a Data-Driven Model and Dempster-Shafer Reasoning

This article presents a new data-driven method for leak localization in water-distribution networks (WDNs). The method uses the information provided by a set of pressure sensors installed in some internal network nodes in addition to flow and pressure measurements from inlet nodes. Pressure measurements are recorded under leak-free network operation, and a WDN data-driven model of the pressure at each sensed node is adjusted. The pressure estimation from this model is complemented by a Kriging spatial interpolation technique to estimate the pressure in the nodes that are not sensed, leading to a pressure reference map. Leak localization is based on the comparison of this reference pressure map with the current pressure map that is obtained by applying Kriging directly to the pressure measurements provided by sensors. The key element in this comparison is the use of the Dempster-Shafer theory for reasoning under uncertainty. The successful application of the proposed methodology to two real-data case studies is presented.This work has been funded by the Ministerio de Econom´ıa, Industria y Competitividad (MEICOMP) of the Spanish Government through the project DEOCS (ref. DPI2016-76493) and by the Catalan Agency for Management of University and Research Grants (AGAUR), the European Social Fund (ESF) and the Secretary of University and Research of the Department of Companies and Knowledge of the Government of Catalonia through the grant FI-DGR 2015 (ref. 2015 FI B 00591). J. Blesa acknowledges the support from the Serra Hunter program. The third author would like to acknowledge ´ the grant from the Innovation Fund Denmark (IFD) under File No. 6155-00002B

Development and Instrumentation of a 2 Meters Length Autonomous Sailboat for the Collection of Oceanographic Data

[Resumen] Esta contribución presenta la construcción y automatización de un velero de 2 metros de eslora concebido para navegar de manera autónoma y llevar a cabo mediciones científicas. Se describe la instrumentación y la recogida de información por parte de los distintos sensores. La transmisión de esta información se realiza en forma de trama al procesador principal, el cual ejecuta un algoritmo de control para generar las órdenes a los servos de los timones y al servo del alerón de la vela. El procesador principal también es el encargado de la presentación de los datos en el formato JavaScript Object Notation (JSON). Se comentan aspectos concretos de la maniobra de la vela y se presenta el resultado experimental de las primeras pruebas de mar.[Abstract] This contribution presents the construction and automation of a 2 meters long sailboat designed to autonomously navigate and carry out scientific measurements. The instrumentation and the collection of information by the different sensors are described. The transmission of this information is carried out in the form of a frame to the main processor, which executes a control algorithm to generate the commands to the rudder servos and the wing aileron servo. The main processor is also responsible for presenting the data in the JavaScript Object Notation (JSON) format. Specific aspects of the maneuvering of the sail are discussed and the experimental results of the first sea trials are presented.Los autores agradecen a la Facultat de Náutica de Barcelona la ayuda económica para la realización del proyecto Sensailor, así como a todos los patrocinadores que han colaborado aportando equipos y dispositivos.https://doi.org/10.17979/spudc.9788497498043